Subgrade planer



3 Sheets-Sheet 1 Filed Dec. 10, 1953 Tom Thomas BY flaw INVENTOR.

MM Attorneys Sept. 1, 1959 T. THOMAS SUBGRADE PLANER 3 Sheets-Sheet 2Filed Dec. 10, 1955 Fig. 3

Tom Thomas" INVENTOR.

Sept. 1, 1959 T. THOMAS SUBGRADE PLANER Filed bee. 10, 1953 3Sheets-Shget 3 Fig. 4

Tom Thomas INVENTOR. BY @MM udflawqH/ag United States Patent fOfificepatented Sept 1,1959

'SUBGRADE 'PLANER Tom Thomas, Houston, Tex.

Application'December 10, 1953, Serial No. 397,429

3 Claims. (Cl. 37-408) "This invention relates to a subgrade planer andmore specifically provides a machine for accurately planing the subgradeof a road bed.

An-object of this invention is to provide a subgrade planer for use inconjunction with roadway forms and having a portion engaging "the uppersurface of such forms and being interconnected with the form engagingmember for accurately and rapidly verticallyadjusting the planer bladewherein a smooth and accurate grade may be planed.

Another object of this invention is to provide a selfpropelled subgradeplaner which is easily operated by a single operator and whichautomatically retains the grade Within a 'very small tolerance or whichmay be a portable attachment'to a bulldozer, motor grader or the like.

A further object of this invention is to "provide a subgrade planer foruse in setting grades to close tolerances wherein light Weight wooden-forms may be employed.

Still another object'of this invention is to provide a subgrade planerwherein the ground surface supports the weight of the machine whereinlight weight wood forms may be employed as the forms do not support theweight of the planer but only the weight of a guide roller.

A still further object of this invention is to provide a subgrade planerwhich is rugged and relatively simple in construction, efficient andaccurate in operation and well adapted for the purposes for which thesame is intended.

These together with other objects and advantages which will becomesubsequently apparent reside in the details ofconstruction and operationas more fully hereinafter described and claimed, reference being had tothe accompanying drawings forming a part hereof, wherein like numeralsrefer to like parts throughout, and in which:

Figure 1 is a top plan view of the subgrade planer of this invention;

Figure 2 is a side elevational view of this invention;

Figure .3 is a longitudinal, vertical section taken substantially alongsection line 33 of Figure 1 showing the details of construction of thesubgrade planer;

Figure 4 is a transverse, vertical section taken'substantially along thecenter line of the machine of this invention showing various details .ofconstruction of the actuating rollers and the planerblade;

Figure 5 is a detail section of one of the planer blade actuatingpistons;

Figure 6 is a detail section of one of the throttling valves and therelationship of the actuating roller to the throttling valve;

Figure 7 is a detail section showing the clutch means for actuation ofthe ground engaging wheels;

Figure 8 is a detail section taken substantially along the center lineof one of the ground engaging driving wheels;

Figure 9 is a transverse, top plan section taken substantially alongsection line 9-9 of Figure 2 showing the details of construction of theplaner blade; and

Figure 10 is a detail section showing the planer blade and the planerblade actuating means.

Referring now specifically to the drawings, it will be seen thatthenumeral 10 generally designates the subgrade planer of this inventionincluding a generally rectangular framemember 12 having a pair of axles14 and 16 thereon in longitudinal spaced relation and parallel to eachother. The axle 14 is supported below the frame 12 by suitable brackets18 and the axle 16 is supported by suitable depending brackets 20. Theaxle 16 carries a pair of ground engaging wheels 22 thereon intransversely spaced relation and a pair of collars 2'4 orientate eachwheel 22 on the axle 16. It will be seen that the wheels 22 aregenerally smooth on their outer surface and act .as supporting wheels. Apair of ground engaging wheels 26 are journaled on the axle 14 intransversely spaced relation and the wheels 26 are orientated by thespacer collars 28. The outer surface of the ground engaging wheels '26is provided with transverse lugs 38 which are generally spiral in natureforming a ground engaging member wherein the wheels 26 are the drivingwheels for the subgrade planer 10. A pair of links 32 are pivotallysecured to the axle 16 adjacent the outer ends of the ground engagingwheels 22 and extend forwardly and are pivotally engaged with lugs 34 oneach end of a planer blade 36 which has a replaceable sharpened edgemember 38 for grading the road bed 40 to an accurate grade. Thesharpened edge member 38 is secured to the planer blade 36 by suitablefastening means 42 wherein the sharpened edge 38 may be replaced asdesired.

A prime mover 44 of any well known type is positioned centrally of theframe 12 and is provided with a transversely extending power take-ohshaft 46 having a pulley 48 mounted rigidlythereon with a sprocket chain50 engaging the sprocket pulley 48 with the sprocket chain 50 passingover the sprocket gear 52 which drives a hydraulic pump 54 having adischarge line 56 and an intake line 58 which is in communication with areservoir tank 60. As shown in Figure 7, each end of the shaft 46 isprovided with a reduced portion 62 having a collar 64 thereon and asprocket gear 66 journaled between the collar 64 and the enlargedportion of the shaft 46. A clutch member 68 is longitudinally slidableon the shaft 42 and keyed thereto by a suitable longitudinal key 70 and'a bellcrank member 72 has a U-shaped end positioned in a peripheralgroove in the clutch member 68 for movement of the clutch member 68 intoengagement with the sprocket 66. The clutch member 68 is provided with aplurality of projecting pins 73 which are selectively engageable with aplurality of blind sockets 74 in the sprocket gear 66. The other end ofthe bellcrank 72 is connected by a connecting link 76 to an operatinglever 78 pivotally mounted on a quadrant 80 having the usual notches 82and the spring loaded dog 84 for selective positioning of the operatinghandle 78. The sprocket gear 66 is engaged by a sprocket chain 86 whichpasses over a sprocket gear 88 rigidly secured to each of the groundengaging wheels 26 thereby driving the ground engaging wheels 26 andpropelling the machine 10 along the ground surface 40. As shown inFigure 3, a brake drum 90 is provided between the sprocket gear 88 andthe drive wheel 26 and a brake band 92 is positioned therearound andindividually connected to a portion of the frame member 94 and aconnecting link 96 which is secured to a brake pedal in a conventionalmanner. It will be understood that a brake assembly is positionedadjacent each driving wheel 26 wherein the device may be directionallycontrolled by manipulation of the brake assemblies controlled by footbrake pedals 100. shown in Figure 3 an operators seat 98 is positionedon the upper surface of the frame 12 wherein the operating handles 78are in position for selective actuation by an operator and by suitablemanipulation the handle 78 and the foot pedal 100, the operator maypropel the device along the ground 40. Along the transverse center lineof the machine and projecting from each side thereof is mounted a roller102 pivotally secured to the blade 36 by a crank-member 104. Theinnermost end of the crank member 104 supported by brackets 105 engagesa valve stem 106 for throttling the flow of pressurized liquid through athrottling valve 108. It will be seen that the throttling valve 108 is,positioned in the hydraulic line 56. It will be understood that byraising and lowering of the roller 102 the throttling valve 108 will beactuated in the following manner. As the roller 102 is raised thethrottling valve is restricted or urged towards the closed position, andas the roller 102 lowers the throttling valve is opened or becomes lessrestricted. As will be seen a hydraulic cylinder 110 is provided and hasa piston 112 slidably mounted therein with the piston having a rod 114extending downwardly through a sealing member 116 in the lower end ofthe cylinder 110 and pivotally connected to the upper end of the planerblade 36 by a suitable pivotal connection 118. It will be seen that thepressure line 56 passes through the underside of the piston 112 whereinpressure will raise the piston 112 along with the piston rod 114 and theplaner blade 36 in an obvious manner.

It will be seen that the cylinder 110 is positioned in the pressure line56 and the pressure line then proceeds to the inlet side of thethrottling valve 108 and thence through a return line to the receiver orreservoir 60. It will be understood that each end of the planer blade 36is connected to a piston rod 114 and each end of the blade isindividually controlled by the control rollers 102 wherein the controlsfor the individual ends of the planer blade are independent of eachother and separately activated by the rollers 102 which engage the uppersurface of the forms 120 which are of light weight wood or othermaterial rather than the usual heavy forms used in roadway work.

From the foregoing construction, the operation of the device will beeasily understood. With the rollers 102 in engagement with the uppersurface of the forms 120 and the grade set, the machine is propelledalong the ground surface 40 and upon hitting a low spot, the frameactually will lower itself thereby raising the roller 102 wherein thethrottling valve 108 will be restricted or moved towards its closedposition thereby building a pressure up in the lower end of the cylinder110 and moving the piston 112 upwardly thereby raising the planer blade36 and accurately grading the desired grade to a very close tolerance.Obviously, upon the ground engaging wheels 26 moving over a high spot,the roller 102 will be relatively lowered thereby opening the throttlingvalve 108 permitting the pressure to return to the tank 60' therebypermitting the gravity of the planer blade 36 to move the blade 36 to alower position towards the desired grade. It will be noted that theplaner blade 36 is necessarily relatively heavy wherein gravity actuatedlowering will be effected. Obviously, suitable control valves may beplaced on the pump 54 and all the various rotating elements may beequipped with suitable grease fittings and the conduits 56 and 58 areequipped with suitable brackets for maintaining the conduits in theircorrect relationship.

In practical operation the subgrade planer of this invention will cut adesired grade within a tolerance of of an inch and at the same timeeliminate the use of the usual metal heavy forms as the only weightresting upon the forms is the weight of the rollers 102. Any materialmeeting the desired specifications of the elements of this invention maybe utilized as may be deemed necessary.

From the foregoing, the construction and operation of the device will bereadily understood and further explanation is believed to beunnecessary. However, since numerous modifications and changes willreadily occur to those skilled in the art, it is not desired to limitthe invention to the exact construction shown and described, andaccordingly all suitable modifications and equivalents may be resortedto, falling within the scope of the appended claims.

What is claimed as new is as follows:

1. A subgrade planer comprising a mobile frame having ground engagingsupporting wheels, a transversely extending planer blade verticallyadjustably mounted on said frame, a fluid pressure actuated piston andcylinder arrangement interconnecting each end of the blade and theframe, a fluid pressure system communicated with each arrangement, acontrol valve for each piston and cylinder arrangement for controllingcommunication of the system therewith whereby the elevation of the blademay be varied, and freely movable means supported from each end of theblade and connected with each of said control valves for actuating saidvalves, said movable means extending laterally outwardly of the framefor engaging a present guide surface for maintaining the blade inconstant relationship to the guide surface without the guide surfacesupporting any of the weight of the blade, each of said movable meansincluding a pivotally supported arm having a guide surface contactelement on the outer end thereof, each of said control valves having anactuating stem connected with the inner end of an arm whereby changes inthe elevational relationship between the blade and guide surface willautomatically change the scope of valve opening.

2. The structure as defined in claim 1 wherein said guide surfacecontact element includes a roller journalled on the outer end of thearm, said arms projecting laterally outwardly of the blade whereby therollers will be disposed out of the path of movement of the blade.

3. The structure as defined in claim 2 wherein said fluid pressuresystem includes a fluid pump mounted on said frame, a prime mover fordriving said pump, said prime mover also supplying locomotive power formoving the planer in a path of movement between the preset guidesurfaces.

References Cited in the file of this patent UNITED STATES PATENTS1,347,008 Brown July 20, 1920 1,849,754 Darrow Mar. 15, 1932 2,043,413Knox et al. June 9, 1936 2,295,519 Millikin et al. Sept. 8, 19422,444,977 Clark July 13, 1948 2,481,679 Miller et al. Sept. 13, 19492,591,502 Bohannan Apr. 1, 1952 2,659,166 Mathias Nov. 17, 1953

